The rheology of oral care composition, particularly dentifrices, is very challenging to formulate. The composition must not be too thick so it can easily dispense out of a tube but thick enough to stand up on a toothbrush without sinking into the bristles. The viscosity of the oral composition must remain stable over time as not to continue to thicken so the oral composition remains easy to dispense during the shelf life. Once dispensed from a container, the oral composition should not be stringy or sticky as to be messy for a consumer to use. The oral composition must also easily disperse once in the mouth and create foam. It is also desired that the oral composition not stick to a sink or leave difficult to remove hard dried residue. In addition to balancing the viscosity and shear thinning to formulate acceptable rheology, the oral composition must also be stable and keep active ingredients, such as fluoride, available.
In addition to the above requirement for a consumer desired oral composition, it is also desired that oral composition be relatively easy to process. The oral composition must have the desired rheology and shelf stability as described above but also be viscous enough to quickly fill the oral composition into a container. It is also desired that the process not require special equipment and that the time to process not be long. It is also desired that the process be economical. Typically, oral compositions are thickened with polymeric thickeners. Polymeric thickeners may require a hydration step which can limit processing flexibility and cause aeration problems. It is also desired that the thickening system of an oral composition be low cost and comprise commonly available ingredients.
Based on the foregoing, there is an ongoing need for improved thickening or structuring systems for oral compositions. There is also the need for economical and convenient processes in making oral compositions. None of the existing art provides all of the advantages and benefits of the present invention.